The present invention relates to telecommunication systems and, more particularly, to a telecommunication system in which full duplex symmetrical circuits are created based on multiple asymmetrical links.
Traditional data and digital telecommunication circuit applications often require a full duplex path. Such applications include, for example, video and multimedia applications for both business and home consumers. Recently, however, in response to the growth of the Internet, several asymmetrical telecommunication standards have emerged. A telecommunication configuration is symmetric if the channel bandwidth needed or provided is the same in both directions. Asymmetric or asymmetrical applications are those in which bandwidth requirements are higher in one direction than the other. Browsing the World Wide Web, for example, requires little bandwidth from the consumer to the content provider (on the order of kilobits per second). Only control information and billing data need to be provided. However, the bandwidth required from the content provider to the consumer is on the order of megabits per second.
One asymmetric configuration and standard which has developed is the asymmetrical digital subscriber line system (ADSL). The ADSL system offers T1 speeds and greater (6 megabits per second) in one direction but speeds less than 5% of T1 in the other direction. ADSL employs discrete multi-tone modulation (DMT) and permits a bandwidth of 6 megabits per second in one direction and 640 kilobits per second in the other. Another asymmetric technology are the X2 modems offered by U.S. Robotics, Inc., which provide 56 kilobits per second in one direction with less than half that in the other direction.
While often adequate for the home market and remote access telecommuting, such asymmetric technologies are limited in that they cannot offer symmetric high speed full duplex circuits. For some users, high speed symmetric circuits are required, as when a user needs to both upload and download full motion video data. However, asymmetrical technologies stand to make inroads into the modem and telecommunications markets because ADSL and X2 modem-type services are priced considerably less than comparable T1 lines, for example.
More particularly, a party needing to transmit digital data at high speeds in both directions typically must pay for symmetrical subscriber services such as T1 services, which typically cost several times what a single ADSL line costs. Similarly, a party such as a home office user needing bandwidth of 56 kbps would be required to pay higher costs for an ISDN line, for example, than for an X2 modem and service.
Accordingly, there is a need to provide high bandwidth telecommunication services to a home consumer or home telecommuter at competitive prices.